


my man and the devil on his shoulder

by orphan_account



Category: Supernatural
Genre: Age Swap, Anal Sex, Bad Dirty Talk, Bottom Sam Winchester, First Time, Loss of Virginity, M/M, Mark of Cain (Supernatural), Needy Sam Winchester, Rough Sex, Teen Sam Winchester, Top Dean Winchester, Underage Sam Winchester, Virgin Sam Winchester, Wincest - Freeform, Witch Curses, i know i'm fucked up
Language: English
Status: Completed
Published: 2020-06-28
Updated: 2020-06-28
Packaged: 2021-03-03 20:53:46
Rating: Not Rated
Warnings: Underage
Chapters: 1
Words: 3,372
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24631873
Author URL: https://archiveofourown.org/users/orphan_account/pseuds/orphan_account
Summary: Sam is hit by a witch curse and wakes up in his 14 year-old self's body. Dean tries to have morals, patience and control but Mark of Cain and Sam don't make it any easier for him.ORin which 14 year old Sam is a needy bitch and practically begs Dean to fuck him?
Relationships: Dean Winchester/Sam Winchester
Comments: 11
Kudos: 106





	my man and the devil on his shoulder

**Author's Note:**

> I'm a SUCKER for underage Sam. There's nothing more to say :(

Dean was jerked awake by a high-pitched scream coming from somewhere in the bunker. His eyes scanned his surroundings first, all was in order, _except._ The spot next to him where Sam was supposed to be was empty. His senses and the mark were alerted because of the potential danger, Sam wasn’t in bed and there was a scream. His hand moved under the pillow to grab his favorite gun with pearly-white hilt. He bolted out of their room, now fully-awake with his hands wrapped tightly around his gun. He ran down the bunker’s mile long hall barefoot to get to the source of the gut-wrenching sound. He heard another yelp along with profanities, the sound was coming from the master bathroom. The closer he got, the clearer he heard the quiet sobs and curses. He couldn’t quite make out whose voice it was but Sam was at the stake so he couldn’t afford spending time on unnecessary details. He turned the safety off, he was ready to ice whatever son of a bitch was inside. He kicked the door open but was struck dumb from what he saw.

‘’What the hell?’’

There was a kid, not over 16 at the best, in the middle of their bathroom with _Sam’s_ clothes dangling from his tiny form.

‘’Who the hell are you? Where is Sam?’’

He was trying to figure out what the fuck was going on. His eyes were tearing the place apart, looking for any sign of trespassing, any trace of blood. The kid slowly turned around to face him with tears in his eyes. His eyes, that very familiar every-color irises on their hazel beds just like-

‘ _’Sammy?_ ’’

He lowered the gun and put it on one of the shelves, his mouth was gaped open wide, never would’ve guessed he’d see this Sam again. He approached to the boy cautiously, he wasn’t sure if he was his Sam stuck in this teenage body or if he was completely that teenage Sam.

‘’It’s me Dean.’’

He put his arms up, gesturing his body. Dean completely forgot how tiny Sam was when he was around this age. Sam’s t-shirt was like a dress for him now, covering all the way down to his bony knees. He was scrawny, nothing but long limbs at everywhere, his unruly shaggy hair and the bangs were back. He knelt in front of him to take a better look at him, he wasn’t hurt, so his scream and the tears filling his eyes, were all from frustration. ‘He had every right to be.’ thought Dean.

‘’How did… that happen?’’

‘’It’s probably the witch we killed. She was doing some spell work when I caught her, must’ve pulled her last stunt on me.’’ He was playing with the hem of his shirt, trying to overcome the embarrassment he was feeling.

‘’What are you now, 15? 16?’’

‘’14.’’ He stroked the soft hair to calm him down a little, he could see Sam shaking. He cupped his cheek, still a little bit chubby with baby-fat, and made him look at him in the eye.

‘’We’re gonna find a way Sammy, I’m gonna fix you, okay?’’

‘’Look at me Dean I’m fucking ridiculous! I’m barely over 5’4’’ and I’m all skin and bones, I can’t even go out like that let alone go hunting!’’

Dean hushed him and pulled him to his chest, wrapping his strong arms around him. He was taken aback when he felt the wetness on his shoulder, yeah Sam may be the _let’s hold hands and talk about our feelings_ type but it surprised Dean to see him cry. He let his arms wrap around his slim waist and lifted the feather-weight boy up.

‘’You listen to me and you listen well, there’s nothing ridiculous about you, you’re still my Sammy. It’s an accident and I’m gonna fix it, capish?’’ Sam nodded and wrapped his legs around Dean’s torso. Since big Sam was stupidly tall and built like a brick shithouse, it felt weird how his legs barely made it all the way around. It was dead of the night, they could find a way to undo this crap in the morning.

‘’Now I’m gonna take you to bed and first thing in the morning we will look for a cure.’’ One of his hands were holding Sam tightly, other one was tracing up and down his spine while he soothingly whispered promises into his ear. Dean laid them down onto the bed, Sam snuggled up to Dean with his head tucked under Dean’s chin.

‘’Good night Dean.’’

‘’Good night Sammy.’’

********************************************************

It turned out there were hundreds of age swapping and transfiguration spells, each of them were made with different ingredients. It could’ve helped them to know at least one or two of the things the witch used but first thing they did was to destroy her altar, which meant all of her stuff including the ingredients she used and her grimoire. There were lots of different spells they could try to undo an age swapping spell but since they didn’t know the exact spell that has caused this, even the slightest wrong move could damage Sam beyond repair. Since that witch was too dead to interrogate and they weren’t known for befriending witches, all they had gotten out of their researches through the internet and Men of Letters’ library was jack with a side of squat. They sent news to their hunter friends, especially to the ones who were hunting witches, so all they could do was to wait for something new.

Meanwhile, Sam was being his usual self. He had his nose in the books, geeking out anything he could get. Other than that, he was considerably _energetic_ due to his age. He was 14, his metabolism was fast enough to burn his bellyful of lunch down within fifteen minutes and he was horny all the damn time.

‘’Ugh I don’t remember it being this out of control. I mean it’s up and down and it’s up again for no reason!’’ Sam tossed the book in his hand aside and leaned back on his chair.

‘’Dude! Too much information.’’ Dean grimaced and turned away but he could feel Sam’s eyes on him. He could hear the wheels in Sam’s head turning.

‘’What?’’ Sam got up from his chair, circled the table and sat down on Dean’s lap, straddling him.

‘’You know, I got my v-card back. Maybe we can take it for a test drive?’’ Dean gaped at him when he got where this conversation was going.

‘’No Sam I’m not fucking a fourteen year old!’’ Dean tried to push him away but he intertwined his ankles with Dean’s legs and ground down on his lap.

‘’I was like what, 17 or 18, when you first fucked me? What’s the difference? Besides it’s still me.’’ Dean took a deep breath and shook his head.

‘’You’re a freaking kid dude that’s the difference. For fuck’s sake Sam I’m trying to have _morals_ , ever heard of it?’’

‘’Yeah like two brothers fucking is so _morally right_.’’ He punctuated his sentence with a roll of his hips. He grabbed Sam by the hips and lifted him off.

‘’Get it out of your horny teenager mind.’’ He quickly left the room and rushed to the bathroom. He was hard and mad at his dick for liking what happened. He unzipped his jeans and pulled them down a little for quick access. He really didn’t want Sam to catch him like this, he didn’t want him to know how much he actually liked the idea.

‘’Fuck, Sammy you’re gonna be the death of me.’’

********************************************************

It’s been a week and there were no news. Everyone was still trying to find something. Sam was getting used to his body, at least he was less bitchy about it. But things weren’t exactly sunshine and rainbows for Dean. He hadn’t left the bunker since he found Sam, other than that one time he went out for a supply run. Sam was in no position to defend himself against the crap they were facing nowadays so Dean was doing his best to not to let him out of his sight, and it was bringing along some problems. The Mark of Cain was getting _impatient_ with each passing second. It’s desire to _kill, destroy and ruin_ was increasing, his hands were itching to grab and squeeze the life of out something. At first it was just about the craving for the physical violence, running through his veins like a liquid fire and getting his blood up. Then slowly, Sam’s physical intimacy put it off the track. It’s focus shifted off from physical violence to sexual hunger. They figured it out a couple months ago, that sex was helping to calm the mark down. And it was working nearly as good as hunting. But now things were different. Sam wasn’t his usual gigantic self, he was just a scrawny teen. Dean could, not could he most certainly would, hurt him. He was reminding himself that Sam was so young, so puny, that he could do more harm than good. The mark was headstrong, it was punishing Dean by getting him more and more aggressive and possessive. He wanted to protect Sam, to take care of him and to cherish him. But the mark was making his blood boil, it was whispering to him, firing him up with dirty encouragement words, telling him to _take Sam, claim Sam and ruin Sam._ He was afraid to do something he’d regret for the rest of his life.

He came up with an alternative, something to help them both to unwind. They could train, both of them could discharge, Dean could calm down and Sam could get stronger. It was a win-win.

‘’Come on Dean, I know you’re taking it easy on me.’’ He ducked down to dodge Dean’s fist. They’ve been sparring for half an hour, Sam was panting and Dean didn’t even break a sweat yet the little fucker had the nerve to call this easy.

‘’Trust me Sammy, it’s for the better. I can rip your throat out with my bare hands and there is a fat chance that I won’t even remember it.’’ Sam parted his feet and bent his knees slightly while keeping his hands level with his cheeks. Dean smirked and thought ‘Nerd, always playing it by the book.’

‘’Bullshit. We both know you won’t hurt me.’’ Sam threw a hook with the arm he had in front, aiming for Dean’s jaw. He caught it expertly and held Sam’s little fist in his hand, he heard Sam’s knuckles cracking.

‘’Yeah I won’t but it will.’’ They kept playing cat and mouse, throwing punches, dodging and parrying them, circling each other what felt like forever. It was enough to ease Sam off, but it was taunting Dean. The mark wanted more, Dean was teasing it, he was offering the thing it desired, a fight, which meant blood, but he was keeping it out of its reach. The veins in his arm were on fire, he could feel the venomous feeling sneaking around. He was so focused on taming his feral side that he didn’t see Sam tripping him up. He found himself on his back with Sam sitting on him. Sam was grinning like a Cheshire cat and Dean was practically growling.

‘’What’s wrong De? Can’t take getting your ass kicked by your baby brother?’’

‘’Get off of me Sam.’’

‘’Why? Are you gonna go and cry?’’ Dean tried to get up but he wiggled his ass to anchor himself down.

‘’Just let me go, I- Sam.. It’s… I don’t wanna hurt you.’’ He put his hands on Dean’s chest and leaned down. Little bastard knew how to push his buttons all at once. Sam was pushing the limits, trying to make Dean give up the last shred of morals he’s been fisting in his hand like they actually mean anything.

‘’I know you’re holding back Dean,’’ Dean hissed when Sam rolled his hips. His patience was wearing thin. The venomous blood running through his veins was pushing him over the thin line between the morality and pure want. All that was ringing in his ears was _to take, take, take, take and take until you’re satisfied, take him-_

‘’Stop it.’’

‘’I won’t break,’’ Sam’s face was an inch away from Dean’s, they were so close, Dean could feel Sam’s hot breath ghosting over his lips.

‘’Sam I’m warning you.’’

‘’I don’t care, I want it to hurt.’’

One look from these eyes with fire and brimstone in them, one lick of that little pink tongue over these thin lips and that was it. Dean was lost. He flipped them over, his big muscular body trapped Sam’s little one under him, the boy was trembling with adrenaline and want. In the end he’s been the one to try and push Dean over the edge. He’s been wearing nothing but too big t-shirts and boxers since they didn’t own any clothes his size, been dropping things on purpose and bending over to pick them up just to wiggle his ass in Dean’s face, been sitting on Dean’s lap every chance he got. The way he’s been whispering pure filth into Dean’s ears with his innocent angelic face and begging him so sweetly, it’s taken everything in Dean to stop himself from bending Sam over the nearest surface and fuck him stupid.

Dean looked down at him and he smiled. Sam was looking at him with so many feelings in his eyes, they were overwhelming Dean in the best way possible. He leaned down and sealed their lips together, Sam opened his mouth to let Dean in with no resistance and melted into the kiss. He was _handing_ the control over to Dean willingly, that pure show of submission went straight to his already hard cock. He ripped the shirt off of Sam and kissed his way down to boy’s nipples. They were already hard, begging to be taken care of and Dean was more than happy to indulge. He sucked and bit them hungrily like a kid in a candy store on a all-free day. The sassy noisy Sam was long gone, he was melting under Dean’s touches and turning into a needy moaning mess. The predatory hunger in Dean’s eyes was making his stomach flutter. His nipples were a deep pink and there were purple marks around them, Dean was taking his time to make sure he claimed every inch of scarless baby soft skin his lips contacted.

‘’Come on Dean, please. I _need_ you.’’ Sam swore he heard Dean growling, this extreme show of need to own was making Sam’s knees weak.

‘’Can’t resist you when you ask so nicely Sammy.’’ He took Sam’s boxers off and tossed it somewhere in the training room. He shimmied himself out of his sweats just enough to free himself, Sam spread his legs wide and reached down to spread his cheeks so he could show Dean his glistening hole.

‘’Fuck, you fingered yourself beforehand? Such an eager slut, I’m gonna fuck you so good that you’ll be sore for days Sammy boy.’’ Dean shoved in with one long thrust, watched his cock disappear into Sam’s tiny body under him. There was something extremely wicked but satisfying about getting fired up by little Sammy’s submission. He thought he could be able to maintain himself, thought it could soothe Mark’s never-ending thirst for destruction in any form but once he got caught into the magnetic field of this sweet mad honey, he had no power over himself to stop.

‘’Never felt this full before De, so good oh my.’’ Sam’s face was a complete picture of bliss, his bite-swollen lips were in a perfect O shape and his eyes were rolled back into his head. His bony fingers were digging into Dean’s shoulders, holding onto him for dear life because Dean was fucking him like the sky was about to fall in a damn minute.

‘’I’m gonna tear you apart Sammy, gonna make you mine _all over again_. You’ll forget your fucking name when I’m done with you.’’ His hole was being torn apart, too-tight ring of muscles were stretched widely around Dean’s cock, feeling every bump and vein on the way so clearly. Every thrust of his hips were ripping a cry or a moan out of Sam, he was nailing his prostate with each thrust so good that it was making his head spin.

‘’You’ve been rambling on all week, begging me to fuck you. Look at you now, you can barely say a word other than my name.’’

‘’Dean, please!’’

‘’Please what?’’

‘’I’m so close, please.’’

‘’What do you want me to do about it, hm?’’ He grabbed Sam’s coltish legs and threw them over his shoulders, leaned forward to fold him in two and to look directly into his eyes. There was something animalistic about Dean’s moves and Sam was loving it. Dean before the Mark was rough too, but he was also concerned 24/7. He’d stop in the middle of everything and check him out for a hundredth time which would end up Sam bitching at him. But _this_ Dean, he knew only to take and take and take. He was a predator, the _king of the jungle_. He still wouldn’t do anything against Sam’s will but he wouldn’t sugarcoat it and second-guess his every move. He would take and claim Sam, he’d make sure Sam know very well that Dean was the one to own him. Knowing this Dean could do anything and everything was enough to make him come. Sam’s breathing quickened, he was blushing and glancing away. Dean knew exactly what was going on, but Sam needed to earn it himself.

‘’You know Dean please, don’t make me say it!’’ He was hard enough to hammer nails with his dick, it was getting more painful with each thrust and Dean was playing with his nipples so good.

‘’Ask me nicely and I’ll do it.’’ Dean kissed him stupid, it was heated but sweet, Sam was vibrating out of his god damn soul into an euphoria. His trembling hands carded through Dean’s hair and hold onto it, his stomach was getting tighter and tighter and everything surrounding him was disappearing until Dean and him were all that was left.

‘’I’m not gonna last longer you better hurry Sam.’’

‘’Can you…’’ He yelped when Dean pulled out and shoved all the way in, his thrusts slowed down into sharp and hard ones. Dean’s pupils were dilated and his lust-clouded eyes were piercing through his own eyes.

‘’Can you choke me?’’

‘’You kinky little slut.’’ Dean grinned and wrapped one of his hands around Sam’s throat, it was way easier than doing this to the gigantic Sam. He was enjoying it as much as Sam, he could feel his rabbit-pulse and the flow of his fresh warm blood. Sam was putting all of his trust and life into Dean’s hands and it was terribly powering. It was enough to push Sam over the edge, his scrawny body was shaking through and through while his cock spurted white stripes all over their chests. His hole tightened around Dean, choking his cock so deliciously that he started to coat Sam’s hot insides, claiming him from the inside out. His boiling blood was cooling down, the itch to destroy was no longer dominant over Dean. He sighed in relief. Their foreheads was touching, sweat dripping from Dean’s to Sam’s, breaths coalescing into one. They were a mess, covered with each other’s sweat and cum and Dean’s body was going limp, crushing the almost 100 lbs boy underneath him.

‘’I’ll get up in a minute.’’

‘’I’m good, but I think you broke my dick. This was the best fucking orgasm I’ve ever had Dean.’’ Dean chuckled and propped himself up on his elbows and carded Sam’s damp hair back.

‘’Glad to know it was worth all your verbal diarrhea.’’ Sam burst into a laughter, Dean stood up and scooped him up. He wrapped his arms around Dean’s neck and kissed his cheek.

‘’Let’s go get cleaned up.’’

**Author's Note:**

> comments are appreciated, hope you like it!


End file.
